Clock display device



May 2, 1950 F. BURCHELL CLOCK DISPLAY DEVICE Filed Nov. 5, 1946 M .4 w 5 n i .m w r v, 3%

Patented May 2, 1950 UNITED STATES PATENT OFFICE CLOCK DISPLAY DEVICE Fiord Burchell, New York, N. Y., assignor to Burohell-Holloway Corporation, New York, N. Y., a corporation of New York Application November a, 1946, Serial No. 701,951

1 4 Claims. This invention relates to display devices embodying the use of polarized light and birefringent material or vectographs and, more particularly, it relates to a display device of this character involving a clock in such a way that its works are used simultaneously for operating the clock hands and for operating necessary movable parts of the display device so that the hands move about a clock face having embodied therewith designs of changing colors or of changing forms or both visible thereon.

An object of this invention is to provide devices of this character that are not only useful but highly ornamental and pleasing to the eye.

Another object of this invention is to provide devices of this character that are simple in construction, easy to assemble and which may be manufactured at comparatively low cost.

Still another object of the invention is to provide display devices of the character described that are particularly useful for advertising display purposes and which embody the use of aclock face and changeable designs associated with the face, whose changes are effected by the use of the clock works or motor that operate the hands of the clock.

Another object of the invention is to provide devices of this character that may be constructed without extensive modification of existing clocks.

To the accomplishment of the foregoing and such other objects as may hereinafter appear, the invention comprises the novel construction and arrangement of parts hereinafter to be described and then sought to be defined in the appended claims, reference being had to the accompanying drawing forming a part hereof, which shows merely for the purposes of illustrative disclosure, some embodiments of the invention,-it being expressely understood. however, that changes may be made in practice within the scope of the claims without digressing from the inventive idea.

In the drawing in which similar reference characters denote corresponding parts:

Fig. 1 is a front eievational view of a device embodying the invention;

Fig. 2 is a vertical section taken along line 2-2 of Fig. 1 and viewed in the direction of the arrows;

Fig. 3 is an enlarged fragmentary sectional view taken along line 3-4 of Fig. l and viewed in the direction of the arrows; and

Fig. 4 is a diagrammatic illustration of the principles of operation embodied in the practice of the invention.

Referring to the drawing l denotes a casing having an open front face defined by a flange I l and a rear wall I 2. An electric clock works or motor l3, for example. of the "Telechron type or any other conventional type of electric clock works or motor is secured suitably as by the screws H to the casing wall l2. This clock motor It has on its shaft its the drive gears G1, Ga, (3: arranged to mesh respectively with gears G4, Ga, Ga and thereby to drive the usual concentrically arranged hollow shafts ll, l8 and a third or inner shaft I! which extend forwardly of the otor I! through an opening it in the wall l2. e minute and hour hands l8 and 20 are Jmounted on the respective hollow shafts I5 and i8 timed for rotation in conventional manner at the forward ends of these respective shafts. The latter and also the forward end of shaft ll extend forwardly of the open face ll of the casing in and through an opening in a covering sheet or member 2|. This sheet 2| preferably is of light transmittin ucent or transpargi t isotropic materiaTsTfch as cellulose acetate or "Vinylite" or of other isotropic translucent or transparent material. The front face of this-sheet 2| serves as a clock dial and is provided with the usual clock face markings such as the numerals and, if desired, minute markings (not shown) and the like.

One or more electric lights 22 are carried in conventional sockets 23 which in turn are supported within the casing Ill behind the covering sheet 2|. The electric power to operate these lights may be provided through a conventional electric circuit (not shown), provided, if desired. with a switch (not shown) for operation from the same electric power source that is utilized to drive the motor ll.

The conventional sweep-second hand of the ordinary electric clock which usually would be mounted upon the innermost shaft ll for rotation with it is replaced by a composite disc or arm 24. Likewise this shaft i1 is geared to run at a faster rate than the single revolution per minute of the usual sweep-second shaft. It is geared to make, for example, six revolutions per minute instead of one revolution per minute. The disc or arm 24 comprises a sheet or length of light polarizing material 25 such as Polaroid mounted upon a co-extensive sheet 28 of isotropic. transparent or translucent supporting material made, for example, of the same material as that of sheet 2|.

' A glass crystal or transparent cover 21 of other suitable material is provided to cover the clock I dial and hands and to enclose the disc or arm 24'.

3 This cover 21 is dish shaped and secured together with the sheet 2i to the annular flange II at the front face of the casing II), for example, by the clamping ring 28.

A second sheet 29 of polarizing material similar to that of sheet 25 is carried within the transparent cover 21 in front of the rotatable sheet 25. This sheet 29 functions as,an analyzer. Suitably secured or cemented to the stationary polarizing sheet or analyzer 29 is a coextensive isotropic sheet 30 of material similar to the sheet 2!. This, sheet 39 which is adapted to lie between thetyvo polarizing sheets 25 and 29 has applied-to it a design D. This design may, forexample be. a 'mosaic-like construction, built up of' hire. fringent elements 49, 4|, etc. Such elements, for example, consist of Scotch cellulose tape? or; other birefringent sheet material arranged in single or in superposed layers. The design. D embodying these elements may, for example, be constructed of birefringent material in any of. the manners described in Burchell and Ivins Patent No. 2,393,968, grantedFebruary 5, 1948.

The design D shown includes also so-called vectographpictures 42, 43 also mounted on sheet 30. The vectographs conventionally are superposed photographic images -visible respectively in lights having diflerent angles of polarization. In the alternative, the design]; may consist either of birefringent elements or of vectographs. If combined, theprocedure, for example, taught in mycopendlngapplication, Serial No. 651,522, filed April 12, 1946, now Patent No. 2,483,314, s e e temb r. .7. 9. 9- mv. b use s. the on ruo io o ma e-#15 The o e. e v r in this specification 9. designDisreferredto, it is to be understood to refer to one consisting either of birefringent elements alone, orof vectp graphs alone or of combinations of birefringent;

elements a d f v osra h n he o s.' e mounted on oneof the other shafts 15 or lBin, addition to-the hands l9- or 20 or the shaft I].

design is to be consideredascontaining elements exhibiting changeablecharacteristicsto the observer when viewed in polarizedlight of varyingpolarity.

the designD assemble withthepolarizing, sheet s y e ien s t so r em n material such as matte cellulose acetate, "Vinylite." or h l k o d naril has a flmn clent expansion. from that of the transparent cover 21. In order, therefofieito mouizit it Madame-germ ,2, o r- 1 vi on danger of etach r n i t because of the diflerent. rates of expansion, aframe-likeinember it is. provided. This frame-likemember is prefer ably f per. fi rr p a ic om o i i r o other flexible or yieldable material. The framelike member 45 has one or more perimetriq l. corrugations 48 provided in its surface andlaterally. op ositely extending peripheral flanges 41, 49. The outermost flange 4] is cemented securely to the inner face of the' crystal 2'! withglue, cement or other adherent of eflective. type. Th5, assembled sheets 29, 30 are dimensioned to overlie the inner flange 49 and the,a,d,1acent fates of 65 the sheet as and the flange 4g are Joined toge her with glue, cement or any. other adherent of effective 99 h flfi lfiq ana -mor s! o h rys l ny emperat re. one ess. s-

l os either!!! h x an ion o mo n. to.- said device. and ex sn i e mea s ecur d o aid.

h he s n o e .1. a. i 'eront ates; produce stresses or strains which are taken up, n. e o uga on Al. Hence. our. tende cies. 9? e ra sm i th h ath". li n or: th 9!.612121;

the sheets 29, 99 are held securely in place on the cover 21 and in front of the rotating polarizing sheet 29. If desired, the design D may be built up on the inner face of sheet 29 and the 5 sheet 99 may then be eliminated.

When the clock motor I! is operated as by being plugged in the conventional electric circult apd,the lights- 22 a1;e.pu, th e composite disc 24 rotates withjhe shaft, I 1, and slmulta neously,

the minute and hour hands I9, 29 move over the mp and: through the cover 21. An observerv E-positmned in front of the cover 21 viewing thetrans nittedlight will see unique changes taking place in the design D. For example, if the detifllkbis built up of birefringent elements only,

the continual change in angle of polarization of 1 118113 m m fld b h o in 5 will eil'ect 'a series of color transformations in. the.

designD visible to heobserver E. Onthe other hand, if the design D is made upoi vectographs, 42, 4; only, oneof the vectograph pictures will.

is pp ar r m e into h se o d. f heve ograph pictures 43 and viceversa during the rota: tion of disc 24. Furthermore, if a. comblnationof bire'ringent material v ctos anhs. i8. used.

m, a. combination of. the two eflects just, described will be seen by the observer, that is, color changes.

will occur while the vectograph pictures. change or merge one intothe other.

The; design 12 may be changed. at any time by.

as removal of-the cover-,2]; and. the positioningof, a

substitutedesignin place of the original one.

Other clock works having three shafts may be.

substituted fortheclockworks l3. Likewise for, more slowly changingefiects, the disc 24. could be could be geared to run more slowly.

Pl as n The t uot re 1 8 itha h e 1188111181 4& in. appearance, has great advertising: value and,

novel;' clocls and; color display device,

may be constructed without extensivempdiflca tion of existing-structures.

While a specific embodiment ofthe invention h s e n s ow it is o b n ers o d ha h n es may b m de n rao coian ar smtemplated. Th re 18 1. ni t im' them-W36 shown and de dish-like casing having an open front, a light;

transmittingisotropic covering for the open front,

alight source supported in said: casing. a clock,- wprks having a driven shaft extending. through said casing and said covering,- a polarizing discmounted on said shaft for rotation therewith, minutes and hour hand shaftssimilarly-extending through-said casing and covering, minuteand:

hour hands mounted on the respective of said two tinned-tin front of said polarizing disc. a design responsive to changes in polarit cf light inter-.. posed between said disc and said polarizing mom,

her. a transparent covering for the front face of p l r in mber ndto sai rans arentver.- ns. for sit in a d o i in mem r in ront of said-polarizin disc.

2. In a device of the character: described, a;

rom he r me-member are eliminated Thin. to. a in aa nen; imam l ght. trmiaittis:

last-named shafts, a polarizing member posi.

translucent covering for said front, a light source supported in said casing behind saidlcovering, a clock works having a driven shaft extending through said covering, a light polarizing disc mounted on said shaft for rotation therewith in front of said covering, a transparent covering positioned in front of the polarizing disc and secured to said casing. a light polarizing member, a frame-like member having a perimetrical corrugation and perimetrical flanges one secured respectively to said polarizing member and the other secured to said transparent covering to mount said polarizing member in front or said polarizing disc and a design positioned to lie between said polarizing disc andsaid polarizing member, said design being composed of elements exhibiting changeable characteristics when viewed in polarized light of varying p larity created by the rotation of said polarizing disc with said shaft.

3. In a device of the character described, a casing having an open front, a light transmitting covering for said front, a light source supported in said casing behind said covering, a clock works having a driven shaft extending outwardly of said covering, a light polarizing member secured to said shaft for rotation therewith in front of said covering, a transparent covering positioned in front of said light polarizing member and spaced there from, a second light polarizing member, an expansible frame secured to said second light polarizing member and to said transparent covering to mount said second polarizing member in front of said first-named polarizing member, and a design positioned to lie between said two light polarizing members, said design being composed of elements exhibiting changeable characteristics when viewed through the second polarizing member in polarized light of Varying polarity created by the 6 rotation of said first-named polarizing member with said shaft.

4. In a device of the character described, a casing having an open front, a light transmitting covering for said front, a light source suppo ed in said casing behind said covering, a clock works having concentric shafts extending outwardly of said covering, a light polarizing member secured to one of said shafts for rotation therewith in front of said covering, time denoting hands secured to others of said shafts, a transparent covering positioned in front of said light polarizing member and spaced therefrom, a second light polarizing member, an expansible frame secured to said second light polarizing member and to said transparent covering to mount said second polarizing member in front of said first-named polarizing member, and a design positioned to lie between said two light polarizing members, said design being composed of elements exhibiting changeable characteristics when viewed through the second polarizing member in polarized light of varying polarity created by the rotation of said first-named polarizing member with the shaft on which it is secured.

FFORD BUROHELL.

REFERENCES CITED The follc ving references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,018,214 Land Oct. 22, 1935, 2,097,123 Hotchner Oct. 26, 1937 2,146,962 Land Feb. 14, 1939 2,165,974 Land July 11, 1939 2,167,463 Register July 25, 1939 2,313,831 Martin Mar. 16, 1943 

